The Facts About Diazinon: Fact Sheet

This fact sheet presents data culled from EPA’s draft risk assessment for diazinon. The risk estimates will change as the manufacturer submits new studies; however, it is highly unlikely that the EPA will find the risks from these uses acceptable.

Indoor Use is Deemed Unsafe for Small Children

Novartis (now Syngenta) announced on July 24, 2000 that it would no longer support diazinon’s indoor uses including greenhouse application. The company cites lack of funds for the required testing, but EWG suspects that Novartis has given up hope in light of the EPA assessment.

EPA's Risk Assessment shows that children are exposed to diazinon at up to 400 times the EPA's safe dose 24 hours after professional treatment in cracks and crevices.

Diazinon can Pollute Surface and Ground Water

Diazinon is the most frequently detected insecticide in US Geologic Survey’s National Ambient Water Quality Assessment (NAWQA) program. It is found in 24 states plus the District of Columbia, including every major river basin. Diazinon has been found in drinking water wells at levels exceeding EPA’s ‘safe’ level. Diazinon could contribute to unsafe drinking water exposures for children.

Diazinon Poses a Risk to Pacific Salmon

Runoff of diazinon has reached unsafe levels in Northwest watersheds creating a threat to salmon populations. Diazinon interferes with juvenile Chinook salmon’s ability to detect alarm chemicals in the water leaving them vulnerable to predator attacks. Since diazinon is a broad spectrum insecticide, it also impacts the insects and other animals on which the young salmon feed. The dose of diazinon inhibits reproductive behaviors and may also cause genetic damage in fish. The EPA has come under a lawsuit for failing to develop a plan to safeguard salmon from pesticides under the Endangered Species Act.

ALL Uses are Currently Deemed Unsafe for the Home Applicator

Source: EPA Review of Diazinon Incident Reports, 1998

Two female gardeners in Singapore knocked over a container of diazinon. After cleaning up the spill, one of the women experienced diarrhea, dizziness, frothing at the mouth, and pulmonary edema requiring a respirator. She later developed acute pancreatitis.

An 18 month old boy in Michigan was accidentally fed "roach milk" (5% diazinon). The boy was taken to the hospital in a coma. He recovered with treatment. (Detroit News, November 29, 1985)

A six-year-old girl had her hair washed for head lice with diazinon. She was hospitalized after full cardiac and respiratory arrest.

Diazinon has been cited in more than 200 lawsuits involving acute poisonings, chronic conditions and at least one death.

Symptoms of Exposure to Diazinon

Exposure to diazinon can result in headaches, diarrhea, or comas depending on the level of exposure. Below is a list of common signs and symptoms of exposure.

Regulatory History